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/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "nsFontMetrics.h"
#include <math.h> // for floor, ceil
#include <algorithm> // for max
#include "gfxContext.h" // for gfxContext
#include "gfxFontConstants.h" // for NS_FONT_SYNTHESIS_*
#include "gfxPlatform.h" // for gfxPlatform
#include "gfxPoint.h" // for gfxPoint
#include "gfxRect.h" // for gfxRect
#include "gfxTextRun.h" // for gfxFontGroup
#include "gfxTypes.h" // for gfxFloat
#include "nsAtom.h" // for nsAtom
#include "nsBoundingMetrics.h" // for nsBoundingMetrics
#include "nsDebug.h" // for NS_ERROR
#include "nsDeviceContext.h" // for nsDeviceContext
#include "nsMathUtils.h" // for NS_round
#include "nsPresContext.h" // for nsPresContext
#include "nsString.h" // for nsString
#include "nsStyleConsts.h" // for StyleHyphens::None
#include "mozilla/Assertions.h" // for MOZ_ASSERT
#include "mozilla/UniquePtr.h" // for UniquePtr
class gfxUserFontSet;
using namespace mozilla;
namespace {
class AutoTextRun {
public:
typedef mozilla::gfx::DrawTarget DrawTarget;
AutoTextRun(const nsFontMetrics* aMetrics, DrawTarget* aDrawTarget,
const char* aString, uint32_t aLength) {
mTextRun = aMetrics->GetThebesFontGroup()->MakeTextRun(
reinterpret_cast<const uint8_t*>(aString), aLength, aDrawTarget,
aMetrics->AppUnitsPerDevPixel(), ComputeFlags(aMetrics),
nsTextFrameUtils::Flags(), nullptr);
}
AutoTextRun(const nsFontMetrics* aMetrics, DrawTarget* aDrawTarget,
const char16_t* aString, uint32_t aLength) {
mTextRun = aMetrics->GetThebesFontGroup()->MakeTextRun(
aString, aLength, aDrawTarget, aMetrics->AppUnitsPerDevPixel(),
ComputeFlags(aMetrics), nsTextFrameUtils::Flags(), nullptr);
}
gfxTextRun* get() const { return mTextRun.get(); }
gfxTextRun* operator->() const { return mTextRun.get(); }
private:
static gfx::ShapedTextFlags ComputeFlags(const nsFontMetrics* aMetrics) {
gfx::ShapedTextFlags flags = gfx::ShapedTextFlags();
if (aMetrics->GetTextRunRTL()) {
flags |= gfx::ShapedTextFlags::TEXT_IS_RTL;
}
if (aMetrics->GetVertical()) {
switch (aMetrics->GetTextOrientation()) {
case StyleTextOrientation::Mixed:
flags |= gfx::ShapedTextFlags::TEXT_ORIENT_VERTICAL_MIXED;
break;
case StyleTextOrientation::Upright:
flags |= gfx::ShapedTextFlags::TEXT_ORIENT_VERTICAL_UPRIGHT;
break;
case StyleTextOrientation::Sideways:
flags |= gfx::ShapedTextFlags::TEXT_ORIENT_VERTICAL_SIDEWAYS_RIGHT;
break;
}
}
return flags;
}
RefPtr<gfxTextRun> mTextRun;
};
class StubPropertyProvider final : public gfxTextRun::PropertyProvider {
public:
void GetHyphenationBreaks(
gfxTextRun::Range aRange,
gfxTextRun::HyphenType* aBreakBefore) const override {
NS_ERROR(
"This shouldn't be called because we never call BreakAndMeasureText");
}
mozilla::StyleHyphens GetHyphensOption() const override {
NS_ERROR(
"This shouldn't be called because we never call BreakAndMeasureText");
return mozilla::StyleHyphens::None;
}
gfxFloat GetHyphenWidth() const override {
NS_ERROR("This shouldn't be called because we never enable hyphens");
return 0;
}
already_AddRefed<mozilla::gfx::DrawTarget> GetDrawTarget() const override {
NS_ERROR("This shouldn't be called because we never enable hyphens");
return nullptr;
}
uint32_t GetAppUnitsPerDevUnit() const override {
NS_ERROR("This shouldn't be called because we never enable hyphens");
return 60;
}
void GetSpacing(gfxTextRun::Range aRange, Spacing* aSpacing) const override {
NS_ERROR("This shouldn't be called because we never enable spacing");
}
gfx::ShapedTextFlags GetShapedTextFlags() const override {
NS_ERROR("This shouldn't be called because we never enable hyphens");
return gfx::ShapedTextFlags();
}
};
} // namespace
nsFontMetrics::nsFontMetrics(const nsFont& aFont, const Params& aParams,
nsPresContext* aContext)
: mFont(aFont),
mLanguage(aParams.language),
mPresContext(aContext),
mP2A(aContext->DeviceContext()->AppUnitsPerDevPixel()),
mOrientation(aParams.orientation),
mExplicitLanguage(aParams.explicitLanguage),
mTextRunRTL(false),
mVertical(false),
mTextOrientation(mozilla::StyleTextOrientation::Mixed) {
gfxFontStyle style(aFont.style, aFont.weight, aFont.stretch,
gfxFloat(aFont.size.ToAppUnits()) / mP2A, aFont.sizeAdjust,
aFont.family.is_system_font,
aContext->DeviceContext()->IsPrinterContext(),
aFont.synthesisWeight == StyleFontSynthesis::Auto,
aFont.synthesisStyle == StyleFontSynthesis::Auto,
aFont.synthesisSmallCaps == StyleFontSynthesis::Auto,
aFont.synthesisPosition == StyleFontSynthesis::Auto,
aFont.languageOverride);
aFont.AddFontFeaturesToStyle(&style, mOrientation == eVertical);
style.featureValueLookup = aParams.featureValueLookup;
aFont.AddFontVariationsToStyle(&style);
gfxFloat devToCssSize = gfxFloat(mP2A) / gfxFloat(AppUnitsPerCSSPixel());
mFontGroup = new gfxFontGroup(
mPresContext, aFont.family.families, &style, mLanguage, mExplicitLanguage,
aParams.textPerf, aParams.userFontSet, devToCssSize, aFont.variantEmoji);
}
nsFontMetrics::~nsFontMetrics() {
// Should not be dropped by stylo
MOZ_ASSERT(NS_IsMainThread());
if (mPresContext) {
mPresContext->FontMetricsDeleted(this);
}
}
void nsFontMetrics::Destroy() { mPresContext = nullptr; }
// XXXTODO get rid of this macro
#define ROUND_TO_TWIPS(x) (nscoord) floor(((x) * mP2A) + 0.5)
#define CEIL_TO_TWIPS(x) (nscoord) ceil((x) * mP2A)
static const gfxFont::Metrics& GetMetrics(
const nsFontMetrics* aFontMetrics,
nsFontMetrics::FontOrientation aOrientation) {
RefPtr<gfxFont> font =
aFontMetrics->GetThebesFontGroup()->GetFirstValidFont();
return font->GetMetrics(aOrientation);
}
static const gfxFont::Metrics& GetMetrics(const nsFontMetrics* aFontMetrics) {
return GetMetrics(aFontMetrics, aFontMetrics->Orientation());
}
nscoord nsFontMetrics::XHeight() const {
return ROUND_TO_TWIPS(GetMetrics(this).xHeight);
}
nscoord nsFontMetrics::CapHeight() const {
return ROUND_TO_TWIPS(GetMetrics(this).capHeight);
}
nscoord nsFontMetrics::SuperscriptOffset() const {
return ROUND_TO_TWIPS(GetMetrics(this).emHeight *
NS_FONT_SUPERSCRIPT_OFFSET_RATIO);
}
nscoord nsFontMetrics::SubscriptOffset() const {
return ROUND_TO_TWIPS(GetMetrics(this).emHeight *
NS_FONT_SUBSCRIPT_OFFSET_RATIO);
}
void nsFontMetrics::GetStrikeout(nscoord& aOffset, nscoord& aSize) const {
aOffset = ROUND_TO_TWIPS(GetMetrics(this).strikeoutOffset);
aSize = ROUND_TO_TWIPS(GetMetrics(this).strikeoutSize);
}
void nsFontMetrics::GetUnderline(nscoord& aOffset, nscoord& aSize) const {
aOffset = ROUND_TO_TWIPS(mFontGroup->GetUnderlineOffset());
aSize = ROUND_TO_TWIPS(GetMetrics(this).underlineSize);
}
// GetMaxAscent/GetMaxDescent/GetMaxHeight must contain the
// BE CAREFUL for rounding each values. The logic MUST be same as
// nsCSSRendering::GetTextDecorationRectInternal's.
static gfxFloat ComputeMaxDescent(const gfxFont::Metrics& aMetrics,
gfxFontGroup* aFontGroup) {
gfxFloat offset = floor(-aFontGroup->GetUnderlineOffset() + 0.5);
gfxFloat size = NS_round(aMetrics.underlineSize);
gfxFloat minDescent = offset + size;
return floor(std::max(minDescent, aMetrics.maxDescent) + 0.5);
}
static gfxFloat ComputeMaxAscent(const gfxFont::Metrics& aMetrics) {
return floor(aMetrics.maxAscent + 0.5);
}
nscoord nsFontMetrics::InternalLeading() const {
return ROUND_TO_TWIPS(GetMetrics(this).internalLeading);
}
nscoord nsFontMetrics::ExternalLeading() const {
return ROUND_TO_TWIPS(GetMetrics(this).externalLeading);
}
nscoord nsFontMetrics::EmHeight() const {
return ROUND_TO_TWIPS(GetMetrics(this).emHeight);
}
nscoord nsFontMetrics::EmAscent() const {
return ROUND_TO_TWIPS(GetMetrics(this).emAscent);
}
nscoord nsFontMetrics::EmDescent() const {
return ROUND_TO_TWIPS(GetMetrics(this).emDescent);
}
nscoord nsFontMetrics::MaxHeight() const {
return CEIL_TO_TWIPS(ComputeMaxAscent(GetMetrics(this))) +
CEIL_TO_TWIPS(ComputeMaxDescent(GetMetrics(this), mFontGroup));
}
nscoord nsFontMetrics::MaxAscent() const {
return CEIL_TO_TWIPS(ComputeMaxAscent(GetMetrics(this)));
}
nscoord nsFontMetrics::MaxDescent() const {
return CEIL_TO_TWIPS(ComputeMaxDescent(GetMetrics(this), mFontGroup));
}
nscoord nsFontMetrics::MaxAdvance() const {
return CEIL_TO_TWIPS(GetMetrics(this).maxAdvance);
}
nscoord nsFontMetrics::AveCharWidth() const {
// Use CEIL instead of ROUND for consistency with GetMaxAdvance
return CEIL_TO_TWIPS(GetMetrics(this).aveCharWidth);
}
nscoord nsFontMetrics::ZeroOrAveCharWidth() const {
return CEIL_TO_TWIPS(GetMetrics(this).ZeroOrAveCharWidth());
}
nscoord nsFontMetrics::SpaceWidth() const {
// For vertical text with mixed or sideways orientation, we want the
// width of a horizontal space (even if we're using vertical line-spacing
// metrics, as with "writing-mode:vertical-*;text-orientation:mixed").
return CEIL_TO_TWIPS(
GetMetrics(this,
mVertical && mTextOrientation == StyleTextOrientation::Upright
? eVertical
: eHorizontal)
.spaceWidth);
}
int32_t nsFontMetrics::GetMaxStringLength() const {
const double x = 32767.0 / std::max(1.0, GetMetrics(this).maxAdvance);
int32_t len = (int32_t)floor(x);
return std::max(1, len);
}
nscoord nsFontMetrics::GetWidth(const char* aString, uint32_t aLength,
DrawTarget* aDrawTarget) const {
if (aLength == 0) {
return 0;
}
if (aLength == 1 && aString[0] == ' ') {
return SpaceWidth();
}
StubPropertyProvider provider;
AutoTextRun textRun(this, aDrawTarget, aString, aLength);
if (textRun.get()) {
return NSToCoordRound(
textRun->GetAdvanceWidth(gfxTextRun::Range(0, aLength), &provider));
}
return 0;
}
nscoord nsFontMetrics::GetWidth(const char16_t* aString, uint32_t aLength,
DrawTarget* aDrawTarget) const {
if (aLength == 0) {
return 0;
}
if (aLength == 1 && aString[0] == ' ') {
return SpaceWidth();
}
StubPropertyProvider provider;
AutoTextRun textRun(this, aDrawTarget, aString, aLength);
if (textRun.get()) {
return NSToCoordRound(
textRun->GetAdvanceWidth(gfxTextRun::Range(0, aLength), &provider));
}
return 0;
}
// Draw a string using this font handle on the surface passed in.
void nsFontMetrics::DrawString(const char* aString, uint32_t aLength,
nscoord aX, nscoord aY,
gfxContext* aContext) const {
if (aLength == 0) {
return;
}
StubPropertyProvider provider;
AutoTextRun textRun(this, aContext->GetDrawTarget(), aString, aLength);
if (!textRun.get()) {
return;
}
gfx::Point pt(aX, aY);
gfxTextRun::Range range(0, aLength);
if (mTextRunRTL) {
if (mVertical) {
pt.y += textRun->GetAdvanceWidth(range, &provider);
} else {
pt.x += textRun->GetAdvanceWidth(range, &provider);
}
}
mozilla::gfx::PaletteCache paletteCache;
gfxTextRun::DrawParams params(aContext, paletteCache);
params.provider = &provider;
textRun->Draw(range, pt, params);
}
void nsFontMetrics::DrawString(
const char16_t* aString, uint32_t aLength, nscoord aX, nscoord aY,
gfxContext* aContext, DrawTarget* aTextRunConstructionDrawTarget) const {
if (aLength == 0) {
return;
}
StubPropertyProvider provider;
AutoTextRun textRun(this, aTextRunConstructionDrawTarget, aString, aLength);
if (!textRun.get()) {
return;
}
gfx::Point pt(aX, aY);
gfxTextRun::Range range(0, aLength);
if (mTextRunRTL) {
if (mVertical) {
pt.y += textRun->GetAdvanceWidth(range, &provider);
} else {
pt.x += textRun->GetAdvanceWidth(range, &provider);
}
}
mozilla::gfx::PaletteCache paletteCache;
gfxTextRun::DrawParams params(aContext, paletteCache);
params.provider = &provider;
textRun->Draw(range, pt, params);
}
static nsBoundingMetrics GetTextBoundingMetrics(
const nsFontMetrics* aMetrics, const char16_t* aString, uint32_t aLength,
mozilla::gfx::DrawTarget* aDrawTarget, gfxFont::BoundingBoxType aType) {
if (aLength == 0) {
return nsBoundingMetrics();
}
StubPropertyProvider provider;
AutoTextRun textRun(aMetrics, aDrawTarget, aString, aLength);
nsBoundingMetrics m;
if (textRun.get()) {
gfxTextRun::Metrics theMetrics = textRun->MeasureText(
gfxTextRun::Range(0, aLength), aType, aDrawTarget, &provider);
m.leftBearing = NSToCoordFloor(theMetrics.mBoundingBox.X());
m.rightBearing = NSToCoordCeil(theMetrics.mBoundingBox.XMost());
m.ascent = NSToCoordCeil(-theMetrics.mBoundingBox.Y());
m.descent = NSToCoordCeil(theMetrics.mBoundingBox.YMost());
m.width = NSToCoordRound(theMetrics.mAdvanceWidth);
}
return m;
}
nsBoundingMetrics nsFontMetrics::GetBoundingMetrics(
const char16_t* aString, uint32_t aLength, DrawTarget* aDrawTarget) const {
return GetTextBoundingMetrics(this, aString, aLength, aDrawTarget,
gfxFont::TIGHT_HINTED_OUTLINE_EXTENTS);
}
nsBoundingMetrics nsFontMetrics::GetInkBoundsForInkOverflow(
const char16_t* aString, uint32_t aLength, DrawTarget* aDrawTarget) const {
return GetTextBoundingMetrics(this, aString, aLength, aDrawTarget,
gfxFont::LOOSE_INK_EXTENTS);
}
gfxUserFontSet* nsFontMetrics::GetUserFontSet() const {
return mFontGroup->GetUserFontSet();
}